11.1: Key Terms

11.1 Key Terms

Woodworking has its own technical vocabulary. Knowing the terms helps you understand drawings, communicate with other woodworkers, follow demonstrations, purchase materials, and work safely.

Use this section as a reference throughout WMT 101 and in later woodworking courses.

A–B

Abrasive — A hard cutting material used to remove small amounts of material from a surface. Sandpaper is made by attaching abrasive particles to a backing.

Air Drying — Drying lumber by stacking it so natural air can circulate around the boards.

Alternate Top Bevel (ATB) — A circular saw blade tooth grind in which alternating teeth are beveled in opposite directions. Commonly used for crosscutting.

Alternate Top Bevel with Raker (ATBR) — A saw blade tooth arrangement combining alternating beveled teeth with a flat-topped raker tooth. Commonly used on combination blades.

Band Saw — A woodworking machine that uses a continuous narrow blade running over wheels. Used for curved cuts, rough shaping, ripping, and resawing.

Bark — The protective outer covering of a tree.

Bill of Materials (BOM) — A list of the parts and materials required for a project, often including quantities, dimensions, rough sizes, board footage, and cost.

Board Foot — A unit used to measure hardwood volume. One board foot equals 144 cubic inches.

Bow — Lengthwise curvature along the face of a board.

Butt Joint — A joint in which two prepared surfaces meet directly without interlocking joint geometry.

C–D

Cambium — The growing layer of a tree that produces new wood and bark.

Caul — A temporary piece used during clamping to distribute pressure, maintain alignment, or protect a project surface.

Check — A crack running along a board that does not extend completely through to the opposite face.

Combination Blade — A circular saw blade designed to perform both ripping and crosscutting reasonably well.

Concave — Curving inward.

Convex — Curving outward.

Crook — Lengthwise curvature along the edge of a board. Sometimes called crown.

Crosscut — A cut made generally across the direction of the wood grain.

Crosscut Blade — A circular saw blade designed primarily for cutting across the grain.

Crosscut Sled — A table-saw accessory that supports and guides a workpiece accurately across the blade.

Cup — Curvature across the width of a board.

Dado — A groove or recess cut across the surface of a board to receive another part.

Density — The weight of a material relative to its volume.

Dry Fit — Assembling parts without adhesive to check fit, alignment, squareness, and assembly sequence.

E–G

Earlywood — The portion of a growth ring produced earlier in the growing season. It generally has larger cells and lower density.

Edge — One of the narrow longitudinal surfaces of a board.

End — The surface across the end of a board where end grain is visible.

End Grain — The exposed ends of wood fibers, usually visible at the ends of a board.

Expansion Slot — A slot cut into a circular saw blade plate to help control distortion caused by heat.

Face — One of the two broad surfaces of a board.

Face Grain — Grain visible on the broad face of a board.

FAS — Firsts and Seconds, a high hardwood lumber grade intended to provide a large percentage of clear usable material.

Figure — The visible pattern created by grain, growth structure, color, rays, and other characteristics of wood.

File — A hand tool with cutting teeth used to refine and smooth wood or other materials.

Flat Top Grind (FTG) — A saw blade tooth grind with flat-topped teeth, commonly used for ripping.

Floating Panel — A solid-wood panel fitted into a frame or groove without being glued around its perimeter so it can expand and contract.

Grain — The arrangement and direction of wood fibers and growth structure.

Groove — A recessed channel cut generally in the same direction as the grain.

Growth Ring — Wood produced during approximately one year of tree growth.

Gullet — The open space in front of a saw blade tooth that provides room for chip removal.

H–L

Half-Lap Joint — A joint in which approximately half the thickness is removed from each of two overlapping parts.

Hardwood — Wood from broad-leafed trees, or angiosperms. The term describes botanical classification rather than actual hardness.

Heartwood — Older central wood in a tree that no longer conducts sap and is often darker than sapwood.

Hook or Rake Angle — The angle of the front face of a saw tooth relative to a radial line through the blade.

Jig — A device used to guide a tool or workpiece during a specific operation.

Jig Saw — A portable saw with a narrow reciprocating blade used for curved, irregular, and interior cuts.

Jointer — A machine used primarily to flatten the face of a board and straighten and square an edge.

Kerf — The width of a cut made by a saw blade.

Kiln Drying — Drying lumber in a controlled environment using circulated heated air.

Knot — A portion of a branch or limb contained within lumber.

Latewood — The denser portion of a growth ring formed later in the growing season.

Long Grain — Wood surfaces where the fibers run generally parallel to the surface, such as the face or edge of a board.

M–P

Medullary Ray / Wood Ray — Cellular tissue extending outward from the center of a tree toward the bark.

Miter Joint — A joint created by joining angled surfaces, commonly two 45-degree cuts forming a 90-degree corner.

Moisture Content — The amount of water contained in wood relative to its oven-dry weight, expressed as a percentage.

Mortise — A recess or opening designed to receive a tenon.

Mortise-and-Tenon Joint — A joint in which a projecting tenon fits into a matching mortise.

Nominal Thickness — A named lumber size that may differ from the actual finished dimension, such as 4/4 hardwood.

Pith — The central portion of the tree around which the earliest growth occurs.

Plan of Procedure (POP) — A planned sequence of construction operations, often identifying the tools or machines required for each step.

Planer — A machine used to make one board face parallel to another and bring lumber to a controlled thickness.

Plainsawn / Flatsawn — Lumber cut with the growth rings oriented generally less than about 45 degrees to the board face.

PVA Glue — Polyvinyl acetate adhesive commonly used for woodworking. Titebond Original and Titebond III are examples used in WMT 101.

Pushstick — A device used to help control a workpiece while keeping the operator's hands farther from a cutter or blade.

Q–S

Quarter Notation — The traditional system for describing rough hardwood thickness, such as 4/4, 6/4, and 8/4.

Quartersawn — Lumber cut so the growth rings are oriented more nearly perpendicular to the board face.

Rabbet — An L-shaped recess cut along the edge or end of a board.

Random Widths and Lengths (RWL) — A common way hardwood is sold, with individual boards varying in width and length.

Rasp — A hand-shaping tool with relatively large cutting teeth used to remove wood quickly.

Reference Edge — A straight, controlled edge used as a basis for later measurements and machining.

Reference Face — A flat surface used as a basis for later measurements and machining.

Relief Cut — A cut made into waste material to make a curved band-saw or jig-saw cut easier to complete.

Resawing — Cutting through the thickness of a board to produce thinner pieces.

Riftsawn — Lumber with growth rings oriented at approximately 45 degrees to the face.

Rip Cut — A cut made generally in the same direction as the wood grain.

Rip Blade — A circular saw blade designed primarily for cutting with the grain.

Rip Fence — The adjustable table-saw fence used to guide material during ripping.

Rough Lumber — Lumber that has not been surfaced smooth after sawing at the mill.

Router — A high-speed cutting tool used for shaping edges, following templates, trimming material, and cutting profiles, grooves, and other features.

Router Table — A stationary setup in which a router is mounted beneath a table with the bit projecting upward.

Sapwood — Younger outer wood that conducts water upward through a living tree.

S1S / S2S / S3S / S4S — Lumber-surfacing abbreviations meaning surfaced one, two, three, or four sides.

Selects — A hardwood lumber grade providing a high percentage of clear material, often in somewhat smaller board sizes than FAS.

Shake — A separation between growth rings.

Softwood — Wood from coniferous trees, or gymnosperms.

Special Setup — A machine operation outside normal use that requires instructor approval before the machine is operated.

Split — A crack extending completely through a board.

Sticker — A small dry strip placed between layers of stacked lumber to provide support and allow air circulation.

Stickering — Stacking lumber with aligned stickers between layers to support the boards and allow air circulation.

Surfaced Lumber — Lumber that has had one or more faces or edges machined smooth.

T–W

Tearout — Damage caused when wood fibers lift and break ahead of a cutting edge.

Tenon — A projecting portion of a woodworking joint designed to fit into a mortise.

Texture — The relative size and uniformity of the cellular structure of wood.

Throat Plate — The removable plate surrounding a blade, bit, or spindle where it passes through a machine table.

Triple Chip Grind (TCG) — A saw blade tooth pattern using alternating tooth profiles, commonly used for manufactured materials and specialized cutting.

Twist — Warp in which the four corners of a board do not lie in the same plane.

Wane — Missing wood or remaining bark along the edge or corner of a board.

Warp — A general term for distortion in lumber, including bow, cup, crook, and twist.

Wood Movement — Dimensional change in wood caused primarily by changes in moisture content.

Working Drawing — A drawing that communicates enough information about a project's size, shape, parts, and construction for it to be built.